1 TC96C55 3A OUTPUT PROGRAMMABLE POWER OSCILLATOR 2 FEATURES GENERAL DESCRIPTION ■ ■ ■ ■ The TC96C555 Power Oscillator is an easily programmed IC that can be used in simple switch-mode power supplies, diode doublers and inverters, and similar circuits where high-current pulses are needed in an economical form. The TC96C555 uses TelCom Semiconductors' new Tough CMOS™ process. The output drive capability is similar to the TC4423/4/5 MOSFET Drivers, which can switch in 25nsec into a capacitive load of 1,800pF. The TC96C555 will not latch up under any conditions within their power and voltage ratings. They can accept, without damage, up to 1.5A of reverse current (of either polarity) being forced back into the output. All terminals are also fully protected against up to 4kV of electrostatic discharge. The peak output is rated at 3A. Split outputs permits driving of an external pair of MOSFETS, with controllable cross conduction between upper and lower devices. ■ Controllable Duty Cycle Wide Operating Range ............................. 5V to 18V High Peak Output Current .................................. 3A High Capacitive Load Drive Capability .................................... 1800pF in 20nsec Short Delay Time ............................. < 150nsec Typ APPLICATIONS ■ ■ ■ ■ ■ Fixed Frequency Power Oscillator Voltage Controlled Oscillator Low Power Buck Regulator Supply MOSFET Driver Simple diode inverters and doublers ORDERING INFORMATION PIN CONFIGURATIONS (DIP and SOIC) Package TC96C555COA TC96C555CPA TC96C555EOA TC96C555EPA TC96C555MJA 8-Pin SOIC 8-Pin Plastic DIP 8-Pin SOIC 8-Pin Plastic DIP 8-Pin CerDIP 0°C to +70°C 0°C to +70°C – 40°C to +85°C – 40°C to +85°C – 55°C to +125°C VR2 1 VIN 2 VREF 3 VR1 4 GND VR2 1 8 GND 7 OUT VIN 2 7 OUT 6 OUT VREF 3 6 OUT 5 VDD VR1 4 5 VDD 8 TC96C555CPA TC96C555EPA TC96C555COA TC96C555EOA FUNCTIONAL BLOCK DIAGRAM +4V 3 VREF 8 1V 2V 3V 4 3V Q1 ISOURCE 7 VIN 2 7 OUTPUT A 2V 1V Q3 VR2 5 6 VDD VR1 4 Operating Temp Range Part No. VREF 3 1 3V Q2 6 OUTPUT B ISINK 5 GND 8 TC96C555-7 10/21/96 TELCOM SEMICONDUCTOR, INC. 4-159 3A OUTPUT PROGRAMMABLE POWER OSCILLATOR TC96C555 ABSOLUTE MAXIMUM RATINGS SOIC RΘJ-A .................................................................... 155°C/W SOIC RΘJ-C ....................................................................... 45°C/W Operating Temperature Range C Version ............................................... 0°C to +70°C E Version .......................................... – 40°C to +85°C M Version ....................................... – 55°C to +125°C Package Power Dissipation (TA ≤ 70°C) Plastic DIP ......................................................730mW CerDIP ............................................................800mW SOIC ...............................................................470mW Supply Voltage ......................................................... +20V Input Voltage, Pin 1 or 4 ................. VDD +0.3 to GND –0.3 Maximum Chip Temperature ................................. +150°C Storage Temperature Range ................ – 65°C to +150°C Package Thermal Resistance CerDIP RΘJ-A ................................................................ 150°C/W CerDIP RΘJ-C ................................................................... 50°C/W PDIP RΘJ-A .................................................................... 125°C/W PDIP RΘJ-C ....................................................................... 42°C/W ELECTRICAL CHARACTERISTICS: unless otherwise specified TA = +25°C with 5V ≤ VDD ≤ 18V. Symbol Parameter Test Condition Min Typ Max Unit (VREF - VR1) / RCHG Fig. 2 (VREF - VR2) / RDIS Fig. 2 5.0 5.0 — — 150 150 µA µA VREF Line Regulation of VREF VDD = 15V, IREF = 10µA VDD = 7V to 18V 3.8 — 4 0.6 4.2 1 V %/V Load Regulation of VREF IREF = 0 to 1mA — 0.1 0.2 %/mA — — 5 % Programmable Current Range Pin 4 Input Current for ISOURCE Control Pin 1 Input Current for ISINK Control Reference Section VDRIFT VREF Drift Over Lifetime TCVREF VREF Tempco — 1100 2000 ppm/°C VR1, VR2 Voltage at Pin 1 & 4 2.85 3.0 3.15 V VREF - VR Voltage Across RCHG and RDIS 0.85 1 1.15 V Vih Pin 2, High Switching Threshold VDD = 15V 1.8 2 2.2 V Vil Vih - Vil IREF Pin 2, Low Switching Threshold Delta High to Low Threshold VREF Pin 3 Short to GND Pin 5 VDD = 15V VDD = 15V VDD = 15V 0.8 0.9 — 1 1.0 8 1.2 1.1 15 V V mA – 55 ≤ Temp ≤ 125°C ELECTRICAL CHARACTERISTICS: unless otherwise specified TA = +25°C with 10V ≤ VDD ≤ 18V: Symbol Parameter Test Condition Min Typ Max Unit Voltage Stability Temperature Stability VDD = 7 to 18V – 55 ≤ Temp ≤ 125°C – – 1 0.4 5 – %/V %/°C Power Supply Current IDD0 ≤ VIN ≤ 3V – 2 3 mA tR Rise Time C1 = 1800pF – 23 30 nsec tF Fall Time C1 = 1800pF – 20 30 nsec tD1 Delay Time C1 = 1800pF – 140 180 nsec tD2 Delay Time C1 = 1800pF – 100 140 nsec VDD – 0.025 – – V Oscillator Power Supply Switching Time1 Output VOH High Output Voltage VOL Low Output Voltage RO RO IPK Output Res Hi State Output Res Lo State Peak Output Current 4-160 – – 0.025 V VDD = 15V VDD = 15V – – VDD = 18V – 3.5 2.5 3 5 5 – Ω Ω A TELCOM SEMICONDUCTOR, INC. 3A OUTPUT PROGRAMMABLE POWER OSCILLATOR 1 TC96C555 ELECTRICAL CHARACTERISTICS: specifications over operating temperature range unless otherwise specified 5.0V < VDD <18V. Symbol Parameter Test Condition Min Typ Max Unit (VREF-VR1) / RCHG Fig. 2 (VREF-VR2) / RDIS Fig. 2 5.0 5.0 – – 100 100 µA µA IREF = 10µA 3.6 – – – – 2.7 0.8 1.75 0.75 0.9 – 4 0.9 0.1 – 1100 3 1 2 1 1.0 – 4.4 1.5 0.4 5 2000 3.3 1.2 2.25 1.25 1.1 18 V %/V %/mA % ppm/°C V V V V V mA 2 Programmable Current Range Pin 4 Input Current for ISOURCE Control Pin 1 Input Current for ISINK Control Reference Section VREF VDD = 7 to 18V IREF = 0 to 1mA VDRIFT TCVREF VR1, VR2 VREF-VR Vih Vil Vih to Vil IREF VDD = 15V Line Regulation of VREF Load Regulation of VREF VREF Drift Over Lifetime VREF Tempco Voltage Pin at 1 and 4 Voltage Across RCHG and RDIS Pin 2, High Switching Threshold Pin 2, Low Switching Threshold Delta High to Low Threshold VREF Pin 3 Short to GND Pin 5 – 55 ≤ Temp ≤ 125°C VDD = 15V VDD = 15V VDD = 15V VDD = 15V VDD = 15V 3 4 Oscillator Voltage Stability VDD = 7V to 18V – 1 8 %/V Temperature Stability – 55 ≤ Temp ≤ 125°C – 0.4 – %/°C Power Supply Current 0 ≤ VIN ≤ 3V – – 4 mA tR Rise Time C1 = 180pF, Fig. 1 – 33 40 nsec tF Fall Time C1 = 1800pF, Fig. 1 – 30 40 nsec tD1 Delay Time Fg. 1 – 180 220 nsec tD2 Delay Time Fig. 1 – 160 200 nsec Power Supply IDD Switching Time1 Output VOH High Output Voltage VDD – 0.025 – – V VOL Low Output Voltage – – 0.025 V RO Output Res Hi State – 4.5 6 Ω RO IPK Output Res Lo State Peak Output Current – – 3.4 2 6 – Ω A NOTE : VDD = 15V VDD = 15V VDD = 18V 5 6 1Switching times guaranteed by design. The typical values are from 125°C measurements. Static-sensitive device. Unused devices must be stored in conductive material. Protect devices from static discharge and static fields. Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only and functional operation of the device at these or any other conditions above those indicated in the Operational Specifications is not implied. Any exposure to Absolute Maximum Rating Conditions may affect device reliability. 7 8 TELCOM SEMICONDUCTOR, INC. 4-161 3A OUTPUT PROGRAMMABLE POWER OSCILLATOR TC96C555 TYPICAL CHARACTERISTICS Fall Time vs. Capacitive Load VDD = 5V, 10V, 18V 500 500 Rise Time (nsec) Fall Time (nsec) Freq = 55KHz Temp = 25°C Freq = 55KHz Temp = 25°C 400 5V 300 200 10V 400 5V 300 10V 200 100 100 18V 18V 0 100 0 100 10,000 20,000 1000 CLOAD (pF) Rise Time vs. Temperature VDD = 5V, 10V, 15V 60 Fall Time (nsec) 5V 30 Fall Time vs. Temperature VDD = 5V, 10V, 15V VIN = 0 – 5V CLOAD = 1000pF 50 40 10,000 20,000 1000 CLOAD (pF) 60 VIN = 0 – 5V CLOAD = 1000pF 50 Rise Tme (nsec) Rise TIme vs. Capacitive Load VDD = 5V, 10V, 18V 40 30 5V 10V 10V 20 20 15V 15V 10 –55 –35 –15 5 25 45 65 85 10 –55 –35 –15 105 125 5 25 45 65 85 105 125 Temperature (°C) Temperature (°C) Delay Time vs. Supply Voltage Temp = –55°C Delay Time vs. Supply Voltage Temp = 25°C 140 350 120 Delay Time (nsec) Delay Time (nsec) TD1 TD2 100 80 60 40 250 200 TD1 150 TD2 100 VIN = 0 – 5V CLOAD = 1000pF 20 VIN = 0 – 5V CLOAD = 1000pF 50 0 0 4 6 8 10 12 Supply Voltage 4-162 300 14 16 18 4 6 8 10 12 14 16 18 Supply Voltage TELCOM SEMICONDUCTOR, INC. 3A OUTPUT PROGRAMMABLE POWER OSCILLATOR 1 TC96C555 TYPICAL CHARACTERISTICS (Cont.) Delay Time vs. Supply Voltage Temp = 125°C 250 TD1 200 Delay Time (nsec) Delay Time (nsec) 250 TD2 150 100 50 4 6 8 200 150 TD1 100 10 12 14 16 3 TD2 50 VIN = 0 – 5V CLOAD = 1000pF 0 VIN = 0 – 5V CLOAD = 1000pF 0 –55 –35 –15 18 125°C Frequency (kHz) 25°C 11.3 11.1 -55°C 10.9 RDIS = 22K RCHG = 44K C = 1000pF 6 8 11.5 85 105 125 4 15V 18V 11.3 10 12 14 16 10.9 VDIS = 22K RCHG = 44K C = 1000pF –55 –35 –15 18 5 10V 11.1 10.7 5 25 45 65 85 105 125 6 Supply Voltage Temperature (°C) IDD vs. Supply Voltage Temp = – 55°C, 25°C, 125°C IDD vs. Supply Voltage Temp = – 55°C, 25°C, 125°C 3000 3000 2500 2500 2000 2000 IDD (µA) IDD (µA) 65 11.7 11.7 4 45 11.9 11.9 10.7 25 Oscillation Frequency vs. Temperature VS = 5V, 10V, 18V Oscillation Frequency vs. Supply Voltage Temp at 25°C, – 55°C, 125°C 11.5 5 Temperature (°C) Supply Voltage Frequency (kHz) 2 Delay Time vs. Temperature VDD = 18V –55°C 1500 25°C 1000 500 25°C 1000 125°C 7 –55°C 1500 125°C 500 VIN = 0V VIN = 3V 0 0 4 6 8 10 12 14 Supply Voltage TELCOM SEMICONDUCTOR, INC. 16 18 4 6 8 10 12 14 16 8 18 Supply Voltage 4-163 3A OUTPUT PROGRAMMABLE POWER OSCILLATOR TC96C555 TYPICAL CHARACTERISTICS (Cont.) IDD vs. Temperature VDD = 5V, 10V, 15V IDD vs. Temperature VDD = 5V, 10V, 15V 2500 2000 15V 15V 2000 10V 1500 IDD (µA) IDD (µA) 10V 1500 5V 1000 5V 1000 500 500 VIN = 3V 0 –55 –35 –15 5 25 45 65 85 VIN = 0V 0 –55 –35 –15 105 125 25 45 65 85 Temperature (°C) VREF vs. Supply Voltage Temp at 25°C, – 55°C, 125°C VREF vs. Temperature VDD = 5V, 10V, 18V 4.2 4.1 4.1 105 125 10V -55°C 4.0 5V 4.0 18V 25°C VREF VREF 5 Temperature (°C) 3.9 125°C 3.8 3.9 3.8 3.7 4 6 8 10 12 14 16 3.7 –55 –35 –15 18 Supply Voltage ROUT vs. Supply Voltage Output HIGH 25 45 65 85 105 125 ROUT vs. Supply Voltage Output LOW 10 7 6 8 125°C 6 125°C 5 ROUT (Ω) ROUT (Ω) 5 Temperature (°C) 25°C 4 –55°C 4 25°C 3 2 –55°C 2 1 VIN = 0V 0 0 4 6 8 10 12 Supply Voltage 4-164 VIN = 3V 14 16 18 4 6 8 10 12 14 16 18 Supply Voltage TELCOM SEMICONDUCTOR, INC. 3A OUTPUT PROGRAMMABLE POWER OSCILLATOR 1 TC96C555 TYPICAL CHARACTERISTICS (Cont.) ROUT vs. Temperature Output HIGH 2 ROUT vs. Temperature Output LOW 7 10 6 8 ROUT (Ohm) ROUT (Ohm) 5 6 5V 4 10V 2 18V 4 5V 3 2 3 10V 1 18V VIN = 0V 0 –55 –35 –15 5 25 45 65 85 VIN = 3V 0 –55 –35 –15 105 125 Temperature (°C) 5 25 45 65 85 105 125 Temperature (°C) APPLICATIONS The oscillator timing can easily be controlled by two external resistors, RCHG and RDIS, and capacitor C. RCHG and RDIS set the two constant current sources for charging and discharging C. The source current is always flowing when in operation. When the capacitor has charged to a 2V threshold, the current sink circuit is enabled to discharge the capacitor to the 1V threshold. When 1V is reached, the current sink turns OFF to start another cycle. Resistor RCHG is connected from VREF at Pin 3 to VR1 Pin 4 to program the charging current. Current is set with resistor RDIS connected from VREF Pin 3 to VR2 Pin 1. Both currents can range from 5µA to 150µA. 4 VDD = 18V +5V TEST CIRCUIT 1µF WIMA MKS-2 8 3 0.1µF CERAMIC 90% 10% 0V tD1 VREF 4 5 INPUT 18V TC96C555 tF 90% tD2 tR 90% 7 2 OUTPUT OUTPUT INPUT 6 0V C1 = 1800pF 1 10% 10% GND 100KHz Square Wave tRISE = tFALL ≤ 10nsec 6 5 Figure 1. Output Switching Time VDD 8 3 VREF 10µF 2V VREF 4V RCHG 4 VR1 1V 2V 3V ISOURCE VIN 1V 7 RDIS 2V 2 VIN Q3 1 VR2 OUTPUT VDD 1V C ISINK 6 Q2 5 OUTPUT GND Figure 2. Fixed Frequency Power Oscillator TELCOM SEMICONDUCTOR, INC. 7 Q1 0V TCHG 8 Figure 3. VIN and Output Waveform 4-165 3A OUTPUT PROGRAMMABLE POWER OSCILLATOR TC96C555 APPLICATIONS (Cont.) This circuit will convert a 6 to 15V input to a 5V output of 200 milliamps. Normal operating frequency is 50kHz. Peak to peak ripple is 50 millivolts. A change from 100mA to 200mA produces a 50mV peak change in VOUT, with recovery in 200µs. The TC96C555 is used here as a duty cycle modulator in a buck output circuit. The source current is modulated to control the duty cycle. Sink current is fixed at 100µA with a resistor (R4) of 10K. Transistor Q1, (2N2907A), is used for current modulation into TC96C555 Pin 4, the charge current program input. Shunt regulator TL431 is used for voltage sense and regulation feedback. The TL431 has an internal reference of 2.495V. Terminal R is compared with this reference to control conduction of cathode C to anode A. R2 and R3 are selected to give proper bias current to the TL431. C2 and R7 are for loop compensation and are optimized for a recovery time of 200µs. The TC96C555 outputs, Pin 7 and 6, are tied together so that when output is HIGH, current conducts from VDD Pin 8 to output Pin 7 to charge the inductor, L1. When output is OFF or LOW, energy stored in L1 will continue to conduct through TC96C555 Pin 6 to the lower internal MOSFET and out to Pin 5, the ground return. This circuit does not have current limiting. A fuse is recommended for protection. Figure 6 shows the duty cycle as a function of the source current. Figure 8 shows the frequency vs control voltage. Maximum Frequency RCHG = 13K, Rdis = 6.8K 900 Frequency in KHz 700 500 400 300 200 100 10 20 30 40 C in pF 50 60 80 100 Minimum Frequency RCHG = 200K, Rdis = 100K 100K Frequency in Hz 10K 1K 100 10 1 0.1 10pF 100pF .001µF .01µF C in pF .1µF 1µF Figure 4. Typical Maximum and Minimum Operating Frequency vs. Capacitor +12V R1 10K C4 .1µF R2 560Ω C5 100µF Q1 2N2907A 8 4 3 R4 10K C6 4.7µF C1 470pF 1 VR1 VDD VREF OUT 7 OUT 6 VR2 VOUT L1, 3mH C3 100µF TC96C555 2 VIN 10K R5 GND 5 C2 .1µF R3, 390Ω 100K R7 C A TL431 R 10K R6 Figure 5. +5V Buck Regulator Power Supply with 82% Efficiency at 200mA Output 4-166 TELCOM SEMICONDUCTOR, INC. 3A OUTPUT PROGRAMMABLE POWER OSCILLATOR 1 TC96C555 By connecting both resistors, RCHG and RDIS, to a voltage source instead of connecting to the 4V reference of Pin 3, one can increase or decrease the output frequency. Increasing the voltage source to 5V will double the oscillator frequency by doubling the voltage across both RCHG and RDIS. Decreasing the voltage source to 3.5V will drop the frequency in half. APPLICATIONS (Cont.) Duty Cycle vs. Charge Current Frequency in kHz 100 16 38 50 38 16 2 Duty Cycle in % 80 3 Voltage Controlled Oscillator RCHG = 51k, Rdis = 25.5k 60 1000K 40 10pF 20 0 10 20 30 40 50 60 70 Charge Current in µA ISINK = 100µA 80 90 100 Figure 6. Duty Cycle vs. Charge Current Frequency in Hz 100K 100pF 10K 1000pF 1K 0.01µF 100 0.1µF 4 10 +12V 3.25V 3.5V 4V Control Voltage 5V 7V 5 Figure 8. Frequency vs Control .1µF 8 CONTROL VOLTAGE SOURCE 3 RCHG 4 2 RDIS 1 C VREF VDD OUT OUT VR1 VIN VR2 7 6 OUTPUT 6 TC96C555 GND 7 Figure 7. Voltage Controlled Power Oscillator 8 TELCOM SEMICONDUCTOR, INC. 4-167